In recent years, control systems are being employed that couple various types of control devices over a network with the aim of minimizing the wiring factory automation (FA) systems. In industrial equipment in particular, a so-called motion controller is utilized for devices for control, by coupling the drivers to drive motors on each axis within the drive system and the input and output devices contained within the peripheral devices by way of a network.
The motion controller device is comprised of a central communication device that controls the entire controller, and plural terminal communication devices that directly drive devices for control such as sensors and actuators; and that is utilized by configuring a network in which the communication lines couple the central communication device and plural terminal communication devices by way of configurations such as multi-drop and daisy chains.
The motion controller device executes control by way of a central communication device and terminal communication device that transmit and receive control information for devices and sensor input information via the network.
The network for this type of motion controller device are often utilized in topologies such as bus or ring type topologies by multi-drop, and these topologies have simple communication control and a simple network configuration.
Currently however, advances in the functions and performance of industrial equipment have led to a greater number of devices for control, and systems are now on a large scale, so that adapting network type controllers utilizing multi-drop to these types of large-scale systems, causes longer communication lines and also complicated controller configurations in systems where the available footprint (surface area) is limited such as in industrial equipment.
To resolve these types of problems network topologies that are configured to allow branch coupling such as by point-to-point topology are considered for use on networks for motion controller devices. However, in view of the restrictions on methods for coupling the communication lines in these types of networks, network topology capable of satisfactory response performance required by each device for control is necessary.
Therefore, a great many man-hours are required when applying motion controller devices utilizing these types of networks to large-scale systems.
Moreover, on these types of networks for motion controller devices, plural communication paths are sometimes configured for one terminal communication device in some cases in order to avoid communication interference. There is for example a technology (Patent Literature 1) for coupling a field bus defined as a single configuration bus and a redundant configuration bus while maintaining the universality of the host (upper-ranking) controller. However, these types of networks not only make the coupling methods for communication lines more complicated and the system structure more complicated, but also require many man-hours for communication settings and adjusting the coupling configuration so as to satisfy the response performance required for each device for control.